Tmail is a program that may optionally be used as a delivery agent. It is not part of Alpine but the source code for tmail is distributed with Alpine. There is a potentially serious buffer overflow bug in the tmail (and dmail) that is distributed with Alpine version 2.00 or lower. Since tmail is not a part of Alpine this is very unlikely to affect you. The problem only applies to system managers who have chosen to use tmail on a Unix system for mail delivery. If you do use tmail, you should install the fixed version (2007d or higher) which is available in the UW IMAP toolkit. When a version of Alpine higher than 2.00 is eventually released the fixed version of tmail will be included there, as well.